Cardiac pacemaker

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Strictly also the biological heart components of the sine knot and the Atrioventrikularknotens are "„natural cardiac pacemaker "“, which are parts of the physiological excitation line system, which expression however completely predominantly used for the artificial.

Newer pacesetters have beyond that further functions:

• Line interference (AV-block) between forecourt and chamber bridge (triggering)
• Impact sequence to the body activity of the pacesetter carrier adapt (frequency-adaptive pacesetter)
• Forecourt rhythm disturbances to avoid help, among other things by (preventive Pacing)
• Heartbeat disturbances of the carrier note (Holterfunktionen)
• with link thigh block and bad chamber function through bi or Stimulation improve the pumping function of the heart (kardiale Resynchronisationstherapie)

Cardiac pacemaker functions are implantiert also in ICDs, in order to bring the heart back into the correct rhythm, after it became "“out-shocked"” from flickering.

Cardiac pacemakers are after long years of the technical improvement meanwhile much secure and well working systems, which practically completely redundant the chronic medicine treatment of slow heartbeat disturbances made. The average age with the Erstimplantation amounts to at present 75 years.

The aggregate, in the vernacular often falsely as battery designation, consists of a lithium iodide battery and electronics, both is accommodated in a common housing. A modern cardiac pacemaker has one function duration between 5 and 12 years, on the average 8 years. Then an aggregate change is accomplished, which became very simple today owing to standardized electrode plug connectors (IS-1-Standard).

Types

There are four different kinds of cardiac pacemakers, which differ after the place of the Stimulation:

• Transkutane Stimulation (external, nichtinvasiver pacesetter)
  • Over large adhesive electrodes a current draw is given by the skin, which also the heart stimulates.
  • Due to the large distance between electrodes and Herze large amperages are necessary, which lead also to an unwanted Stimulation of the skeletal musculature.
  • Only in emergency meaningfully and practicably
• Stimulation
  • Minimalinvasives procedure, with which an electrode is pushed by the esophagus up to the height of the heart.
  • The Stimulation is very painful and therefore for diagnostic purposes is very rarely, predominantly accomplished (due to the atrialen situation a better differentiation of forecourt and chamber action is possible).
  • Procedure did not find a substantial spreading.
• Passagere intrakardiale Stimulation
  • Over a Vene is inserted an electrode into the right heart.
  • With operations at the open heart the electrode is fixed directly at the heart.
  • Generation of pulse is made by an external Stimulator.
  • Only to the temporary therapy due to risk of infection.
• Intrakardiale Stimulation by implant
  • Cardiac pacemaker becomes above the right or left chest underneath the mostly under the skin (subkutan) or with very hageren patients also under the large chest muscle implantiert.
  • Electrodes are led to the right forecourt and/or right ventricle (with the pacesetter a 3 becomes. Electrode over right forecourt and the Koronarvenensinus to the Posterolateralwand of the left ventricle advanced).

Structure

A pacesetter system essentially consists of 2 components:

• The battery with electronics (aggregate); today excluding lithium batteries are used, the first cardiac pacemakers used Akkus, which had to be loaded after few hours enterprise from the outside, then mercury oxide zinc primary batteries used, which did some months up to 3 years service and because of the electrolyte with difficulty hermetically closely to be gotten were, a short time before the triumphant advance of the LiJ battery also radioisotope generators were blocked, the plutonium contained.
• The pacesetter electrode (also probe called)

Electrodes

• unipolar
• bipolar
• Anchor electrodes
• Screwing electrodes
• straight
• preformed
• VDD electrodes

Types of permanent cardiac pacemakers

NBG Schrittmachercode

The pacesetters offered today leave themselves, who since 1988 valid and 2002 revised NBG code (NASPE/BPEG gene Eric Pacemaker code) following, into several groups to divide, which with maximum five (usually only the first three) are shortened/designated letters.

The first letter gives information over the Stimulationsort. The letters orient themselves thereby at the anatomical situation of the electrode. "“V"” does not stand A"” for Stimulation in the ventricle (Herzkammer), for "“for Stimulation in the atrium, "“D"” (dual) for Stimulation in both heart ranges, "“S"” (single) for a Einkammerstimulation in atrium or ventricle and "“0"” for "“a Stimulation"”.

The second letter indicates the detection place. Here "“V"” are likewise used for detection in the ventricle, "“A"” for detection in the atrium, "“D"” (dual) for detection within both heart ranges, "“S"” (single) for an a chamber detection and "“0"” for "“no detection"”.

The third letter indicates the mode of operation of the pacesetter. One differentiates between "“I"” (Inhibited) and "“T"” (Triggered): In the inhibierenden mode the pacesetter can suppress the delivery of an impulse with own cardioactivity, in the triggered mode leads a noticed signal to the impulse delivery. "“D"” (dual) is called also here again that both modes are supported in each case and "“0"” that none is supported modes.

The fourth letter describes the programmability, telemetry and frequency adaptation. "“it means 0"” that the pacesetter is not programmable. With "“P"” (Programmable) pacesetters, the one programmability of maximally two functions are named permit and "“M"” (Multi programmable) such by more than two functions. "“C"” (Communication) indicates the possibility of the data telemetry and to "“R"” (rate modulation) the possibility of the adjustment of the pacesetter frequency to an load-induced signal. Since the revision of the NBG Schrittmachercodes 2002 are no longer usable "“P"”, "“M"” and "“C"” officially, particularly since these functions became with each modern cardiac pacemaker a matter of course.

The fifth and last letter designates the place of the Multisite Stimulation. "“A"” means Stimulation at more than one place in the right atrium (or Stimulation in the right and left atrium). "“V"” stands for the Stimulation to more than one place in the right ventricle or Stimulation (Stimulation in the right and left ventricle). "“D"” stands for Multisite Stimulation in atrium and ventricle. "“no Multisite Stimulation means 0"”, neither in atrium nor in ventricle before the revision of the pacesetter code 2002 showed the fifth letter the anti-tachycardiac function. "“no anti-tachycardiac function, "“P"” (Pacing) means 0"” anti-tachycardiac Stimulation, "“S"” (Shock) and "“D"” (dual) Pacing and Shock. Occasionally this outdated nomenclature is still used.